The World Health Organization says that Taiwan's SARS outbreak earlier this year affected only half as many people as originally reported.

The U.N. health agency on Friday made dramatic revisions to Taiwan's official SARS figures after tests showed many patients had other ailments and not Severe Acute Respiratory Syndrome.

Hospitals in Taiwan reported a total of 682 SARS cases earlier this year. But retrospective analysis now shows that only 346 were infected. The number of deaths attributed to SARS was also revised downward.

World Health Organization Pacific spokesman Peter Cordingley says many patients might have had other types of viral pneumonia.

"Taiwan, like all the other places that were affected by SARS, has been approached by the WHO with a view to producing a final tally of the SARS outbreak," he said. "We've asked everybody to do retro diagnosis of cases to see if they can establish if all the deaths were actually caused by SARS."

Mr. Cordingley says that Taiwan and Hong Kong are two places where many people said to have died from SARS are now classified as having died from underlying diseases such as heart conditions or liver ailments.

Taiwan's SARS death toll, which originally listed 180 victims, is now just 37 deaths.

In Hong Kong, the government says the territory's death toll has gone down to 159, but the WHO figures still say there were 299 SARS deaths.

The statistical revisions were released around the same time as an independent report outlining the shortcomings of the Hong Kong government's handling of the crisis. The revisions and the report both angered friends and families of victims.

Global figures on SARS are also reflecting the retrospective analysis. The new numbers show the U.N. agency counting more than 8,000 SARS victims and about 770 deaths. Originally the WHO reported more than 84,000 cases and 900 SARS-related deaths.